mypy exclude regex does not work when removing mid-level directory.

[Victorlouisdg]

When you remove de intermediate package-name from the default structure repository-name/package-name/python_package_name, the test folder ends up in repository-name/test. This causes the regex for the mypy in the setup.cfg not to exclude it anymore.

[Victorlouisdg]

I believe changing the regex from:

exclude = .*\/((test|build)\/.*|setup.py)

to

exclude = .*((test|build)\/.*|setup.py)

Handles both cases (i.e. keeping and removing the mid-level directory).